[HCARC] One last Question

[Gary and Arlene Johnson]

What does it mean to "work an antenna against ground".  This is another one of those seemingly innocuous statements I see in the antenna book.  It assumes that everyone knows what "working against a ground" means.  Is it the same as grounding an antenna??  If all antennas are to be grounded, why make the statement??

You usually see the statement in context like this "this antenna can be used on 160 meters if worked against a ground".

Gary J
N5BAA